package com.time.gateway.exception;

import cn.dev33.satoken.exception.SaTokenException;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.time.gateway.constants.GatewayConstant;
import com.time.gateway.entity.Result;
import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.web.reactive.error.ErrorWebExceptionHandler;
import org.springframework.core.io.buffer.DataBufferFactory;
import org.springframework.http.MediaType;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

/**
 * 网关全局异常处理类
 *
 * @author: HuangQi
 * @date: Created in 17:18 2025/8/27
 * @description: 网关全局异常处理类
 */

@Component
@Slf4j
public class GatewayExceptionHandler implements ErrorWebExceptionHandler {

    private ObjectMapper objectMapper = new ObjectMapper();

    @Override
    public Mono<Void> handle(ServerWebExchange serverWebExchange, Throwable throwable) {
        log.error("GatewayExceptionHandler.handle.throwable:{}", throwable.getMessage());
        ServerHttpRequest request = serverWebExchange.getRequest();
        ServerHttpResponse response = serverWebExchange.getResponse();
        Integer code = GatewayConstant.SUCCESS;
        String message = "";
        if (throwable instanceof SaTokenException) {
            throwable.printStackTrace();
            code = GatewayConstant.UNAUTHORIZED;
            message = GatewayConstant.MSG_UNAUTHORIZED;
        } else {
            code = GatewayConstant.SERVER_ERROR;
            message = GatewayConstant.MSG_SERVER_ERROR;
        }
        Result result = Result.fail(code, message);
        response.getHeaders().setContentType(MediaType.APPLICATION_JSON);
        return response.writeWith(Mono.fromSupplier(() -> {
            DataBufferFactory dataBufferFactory = response.bufferFactory();
            byte[] bytes = null;
            try {
                bytes = objectMapper.writeValueAsBytes(result);
            } catch (JsonProcessingException e) {
                e.printStackTrace();
            }
            return dataBufferFactory.wrap(bytes);
        }));
    }
}
